Intercooler CDTI 3D printed patch repair

Retap · 22nd May 2024, 15:48

My post from yesterday given its own thread so it doesn't go missing again.. With ref to this older thread:
https://www.the75andztclub.co.uk/for...68372#poststop

So, my ZTT Nigel has a poorly inter cooler. The mounting lug on the drivers side is ripped off clean some time ago and was glued back in with pound shop epoxy which has failed after 18 months or so see photo below. We had a miserable drive to the peak district last weekend where i i endevoured to stay at or below 2000 RPM but had to drop down to 2nd gear and go to 3000rpm to get up a nasty long hill it was not pretty with smoke emitting from exhaust as reported by my son who was told not to worry unless flames start happening lol. BTW the MAF is a new Bosch so its unlikely to be that.... (he says)

Having been learning 3D printing the last year i decided to make a simple patch knowing that a very strong composite solution could be obtained using PETG and good quality Epoxy. The great thing about the 3D printing is that there are gaps in the print between the layers and the epoxy can fill those making a very strong composite material so lets test it!

Cleaned up, de greased with Isopropyl alcohol and prepped for patching (almost)

The tools

The patch

The patch was printed flat 8 layers @ 0.2mm layer height using PETG (same as plastic drinks bottles) and then warmed gently both sides using the butane torch and pressed against the area to be patched to shape it and form the end curve as this is the strongest way to do it thinking about the strength of the grain i.e. the layers in the printed patch for strength. Accidentally discovered the inner edge slips into the gap of metal that presses the plastic together for extra strength.

Remove and clean patch and inter cooler area again then mixed up epoxy and coated the inside of the patch then let it go tacky and press onto intercooler it took 10 minutes to get tacky, result below.

To finish i held the patch for 5 minutes with gloves then let is set for another 20 mins whilst i mixed more epoxy to do an over coat and seal the edges.

Finished job

I will wait 24 hours now before testing this so it sets hard, i have good expectations it will last well but only time will tell. It is a very strong composite patch with 3900PSI JB plastic weld epoxy. PETG material used to make the patch melts around 180C and was printed at 235C. ABS materials are available for printing bit i cannot print that yet as the hot end of my printer is not adequate.

The lug is still in my hand and i am thinking of cutting it down and epoxying ontop of the patch to secure the intercooler properly but its been off for a while and i have no idea if thats good or bad.

Retap · 22nd May 2024, 15:51

If any members interested the patch held nicely today around 20 hours after fitting in the last of the weeks sunshine yesterday. Today its grey, wet and dull but had to go out, given weather kept it calm didnt go above 2000RPM but all power restored very nice getting pulled up hills again in 4th.

Will update again when if it fails.

Any members want a patch PM me its free just postage cost unless thousands ask lol.

Arctic · 23rd May 2024, 00:57

HI John.
Nice work and i hope it lasts for you, which i think it will, this could save a lot of intercoolers has they are no longer available

22nd May 2024, 15:48	#1
Retap Loves to post MG ZT-T CDTi Join Date: Sep 2020 Location: Lincs Posts: 300 Thanks: 73 Thanked 51 Times in 44 Posts	Intercooler CDTI 3D printed patch repair My post from yesterday given its own thread so it doesn't go missing again.. With ref to this older thread: https://www.the75andztclub.co.uk/for...68372#poststop So, my ZTT Nigel has a poorly inter cooler. The mounting lug on the drivers side is ripped off clean some time ago and was glued back in with pound shop epoxy which has failed after 18 months or so see photo below. We had a miserable drive to the peak district last weekend where i i endevoured to stay at or below 2000 RPM but had to drop down to 2nd gear and go to 3000rpm to get up a nasty long hill it was not pretty with smoke emitting from exhaust as reported by my son who was told not to worry unless flames start happening lol. BTW the MAF is a new Bosch so its unlikely to be that.... (he says) Having been learning 3D printing the last year i decided to make a simple patch knowing that a very strong composite solution could be obtained using PETG and good quality Epoxy. The great thing about the 3D printing is that there are gaps in the print between the layers and the epoxy can fill those making a very strong composite material so lets test it! Cleaned up, de greased with Isopropyl alcohol and prepped for patching (almost) The tools The patch The patch was printed flat 8 layers @ 0.2mm layer height using PETG (same as plastic drinks bottles) and then warmed gently both sides using the butane torch and pressed against the area to be patched to shape it and form the end curve as this is the strongest way to do it thinking about the strength of the grain i.e. the layers in the printed patch for strength. Accidentally discovered the inner edge slips into the gap of metal that presses the plastic together for extra strength. Remove and clean patch and inter cooler area again then mixed up epoxy and coated the inside of the patch then let it go tacky and press onto intercooler it took 10 minutes to get tacky, result below. To finish i held the patch for 5 minutes with gloves then let is set for another 20 mins whilst i mixed more epoxy to do an over coat and seal the edges. Finished job I will wait 24 hours now before testing this so it sets hard, i have good expectations it will last well but only time will tell. It is a very strong composite patch with 3900PSI JB plastic weld epoxy. PETG material used to make the patch melts around 180C and was printed at 235C. ABS materials are available for printing bit i cannot print that yet as the hot end of my printer is not adequate. The lug is still in my hand and i am thinking of cutting it down and epoxying ontop of the patch to secure the intercooler properly but its been off for a while and i have no idea if thats good or bad. __________________ ZT-T Mk2 Jobs to do: Renew auxiliary drive belt # Replace driver door lock actuator # Refurbish wheels Last edited by Retap; 22nd May 2024 at 15:55..

22nd May 2024, 15:51	#2
Retap Loves to post MG ZT-T CDTi Join Date: Sep 2020 Location: Lincs Posts: 300 Thanks: 73 Thanked 51 Times in 44 Posts	First test drive success If any members interested the patch held nicely today around 20 hours after fitting in the last of the weeks sunshine yesterday. Today its grey, wet and dull but had to go out, given weather kept it calm didnt go above 2000RPM but all power restored very nice getting pulled up hills again in 4th. Will update again when if it fails. Any members want a patch PM me its free just postage cost unless thousands ask lol. __________________ ZT-T Mk2 Jobs to do: Renew auxiliary drive belt # Replace driver door lock actuator # Refurbish wheels Last edited by Retap; 22nd May 2024 at 15:54..

23rd May 2024, 00:57	#3
Arctic Give to Learn Freelander 2 Join Date: Aug 2010 Location: West Midlands Posts: 18,822 Thanks: 1,155 Thanked 6,407 Times in 3,874 Posts	HI John. Nice work and i hope it lasts for you, which i think it will, this could save a lot of intercoolers has they are no longer available __________________ Arctic Givology Learn to Give Everything is Achievable ad altiora tendo. Check out our Nano meet dates http://www.midlandsnanomeets.co.uk/ http://www.the75andztclub.co.uk/index.php?thepage=howto " You do the work , we supply the expertise "